The strategy marks a shift from crackdowns over the past year that mainly targeted companies using unlicensed software, Ahmad Dahuri Mahmud, the Domestic Trade Ministry's deputy director general of enforcement, said Friday.

The current clampdown started Thursday with the arrest of a store owner in a Kuala Lumpur suburban shopping mall. Officials seized three computers with pirated versions of Windows XP from a 28-year-old suspect's premises, Ahmad Dahuri said.

The man is expected to be charged under copyright laws that provide for maximum prison sentences of five years and a fine of up to 20,000 ringgit ($5,700) per infringement.

Officials were also investigating claims by the public that some dealers have been loading pirated versions of beta copies -- unofficial versions released for tests -- of Windows Vista, Ahmad Dahuri said.

"We haven't found (pirated copies of) Windows Vista yet, but there have been complaints," Ahmad Dahuri said. "The government has no choice but to hit hard at the source as software piracy at the retail end has become rampant."

Windows Vista, Microsoft's long-delayed operating system upgrade, was released with much fanfare to consumers at the end of January.

Ahmad Dahuri did not say how many outlets were suspected to carrying illegal software, but stressed that "a high percentage" of computer retailers were believed to be involved.

Some 60 percent of all software used in private businesses in Malaysia was illegal in 2005, the latest year for which figures are available, according to the Business Software Alliance, an anti-piracy watchdog. Malaysia's software industry lost $149 million to piracy that year.